Perhaps you should try some spelling variations:
ve triet » va trien, su triet
van hanh » van thanh, ban hanh, van anh
luc van » luoc van, luu van, duc van
cau luc » cau truc, cau phuc
sach ty » sach y, sach tu, sach thu
co sach » bo sach, cuon sach, hoc sach
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va
vi ve » va ve, gi ve, ve ve

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: co sach ty ((nang xa) or (nang ma)) hoi. ((hieu va) or (hieu qua)) cau luc van hanh vi ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ty ((nang xa) OR (nang ma)) hoi. ((hieu va) OR (hieu qua)) cau luc van hanh vi ve triet.
• Adding a wildcard symbol may retrieve word variants: co sach ty ((nang xa) or (nang ma)) hoi. ((hieu va) or (hieu qua)) cau luc van hanh vi ve triet*.